Method of forming molded articles



April 18, 1933. J. J. ZELENKA METHQD OF FORMING MOLDED ARTICLES Filed Jan. 1929 JOSEPH JAMES znnnnxatr LAVGRANGE, 13115 0: sei eiioatoiwnm ma;

of pressure an-dheat, followed'by a cooling such a process .is performed withpolished V to the gloss formedby"thepolished iniolds the app-earance ofthe inol-dedparts sufiered; p p and the workof re-polishing'made the manu .1

may be produced I and to improve the appearance and uniforma ity of articles molded from ing line between the molding die member's,

'ing open tion Was necessary toeli ninate the spits andrregularities formed at thepoint Where the fin Was removed, an-dithis grinding' H finish obtained by polishing operationsfis Patented Z i i COMPANY; INCORPORATED," or NEW YORK} METHOD-OE: FoitMiNe-ironnnn; mTIcLEs Application filed January 2, I i I This invention relates to a method ofmold-k p I ea-@1 11 t at it m y; b mbr e y refil ing articles, and more particularly to a meth od of molding articles from phenol plastic:- and similar materials whereby such articles while preserving their orig- Objects of the invention. are to provide an v 1 improved methodwhere'by articlesmayloe produced more economically andefliciently; 1

phenol plastic I and similarmaterials. a i The manufaeture of molded articles fromf phenol plastic and similar ,materials or di narily involves thesimultaneous application step While maintaining the pressure; Where dies, an autogenous.outercoating or integu-y 1 ment isformed on the article which greatly; set V ormed iacjcor- V enhances its appearance. In molding plastic'inigfthe invention. I by a V 4 i H articles of various shapes in the past, athin jThe 'invention lu strate'd, and' gvvill fbg; fin hasunavoidably been formed at the partdescribed;vvitlr specific reference toil f-tele "P1 911 ndset, b t.wi labeufid s and particularlywvhere this fin Was formed on a curved surface ithas'been diflicultto remove it without meaning the" autogenous finish of he adjacent surfaces, sinc ea grind;

operationusually marred'the adjacentpora, tions .ofthe' surface With'the resulfjth-at-all .or a great portion of the [entire surfaceo'li b the article had, to be rev-polished; Since'any inferior both in-i appearance and durability l c facture of "su h artsi unduly expensive. 1 7

' Also,rvaryinggam-ounts ofmaterialwer'e'nec l Vessarily removed in eliminating the pits and;

irregularities, 'Withthe vresult that the Shap v ofthe finished articles varied considerably,

In' the presentinventiomf' the above dis advantages are avoide'd by shaping the mold J V Whenthemoldedarticle isremoved fromthe mold, the fi'nsi'15 are removed by breaking 7 subjected to the usual molding operations,

ter cap 24 shown in Fig. 4 is formed in a similar manner. v a

In practicing the invention, the ELItlCll-Z'IS i preferably comprising heat and pressure. 7

r them off, the outer edge oftaperedportion' 19aforming a; line of; weakness at which the L 1 break; will usually occur. The outer surface 20 of theridges' l l is then smoothed by I grinding it down as indicated inTFig.'r3, a r0 tary stone 22 or other suitable abrasive apby a buflinglo'r polishing operation. i This ishing the new surface of, the ridge thus formed.

Inwitness whereof, I hereunto subscribe 7' my name this 24th day of DecemberA.

- JOSEPH JAMES ZE ENKA,

r paratus being used,,and followed if desired -l results, in ithelsurface 'receiving 'a finish which maybe considerably duller than the native gloss of the resti'of the molded'ar'ticle,

. but inasmuch asf the ridge is'symmetrically placed with respectto the remainderof the ,article it forms a. regular design which in no I way detracts from the appearance .of'the car.-

ticle. This grinding andpolishing, being performed on a raised surface, need not mar theadjacent surface'sof the article. Finally,

the surface20may, if d'esired,b e finished by applying a suitable stain or varnish, in which a I case no buflin'g .or polishing isnecessary. Y

When the handle 12, receiverlcap lff and transmitter cap 241; are assembled, the jarrangementof theridges 14-is suchthatfthey are in substantial parallelism to'eachother and to thestructural division lines 26 of the instrument, which arrangement causes themto 1 blendinto thelinesof the general design in such amanner that they do not detract from,

but rather add to,the "appearance oi"; theas v sembled instrument.

Various modifications maybe made in the method herein disclosed without departing from the spirit of the invention as defined in thefollowing cl'aiins,

' What is claimed is:

1. The method ofp'roducing'a molded arti V ole of ornamental appearance which corn prises molding the article in a mold having a i recesslocated within the'article forming cavity mold at the parting line-thereof to' form a r ridge around the article'fwith a fin or excess inaterialintegral therewith, holding the'article in the mold until the material thereof'is r. iis r.

1 completely finishedand set, removing'thearticlefrom the mold, andrenioving thefin of excess material and a part of the'ridgeQ i l V ;1 n the mold an thematerial thereof is {'1 completely finishedand set, removing the ar- V ticle from the 'mold', removing the fin of ,ex-

cess material and a part of. the ridge, and 1501- iio 

